# black hole
## English
### Alternative forms

* black-hole
* blackhole

### Etymology

In reference to celestial bodies, physicist Hong-Yee Chiu attributed the term to his colleague Robert H. Dicke, who stated around 1960–1961 that the objects were "like the Black Hole of Calcutta". The first known usage in print was by journalist Ann Ewing in 1964. Widespread popularization of the term is generally credited to a 1967 lecture by physicist John Wheeler.

### Pronunciation

* (US) IPA: /blæk ˈhoʊl/
* (UK) IPA: /blæk ˈhəʊl/
* Audio (US):(file)

### Noun

black hole (plural black holes)
* A place of punitive confinement; a lockup or cell; a military guardroom. [from 18th c.]
** 1808–10, William Hickey, Memoirs of a Georgian Rake, Folio Society 1995, p. 282:
    ‘I will convince you that I do know [my duty] by clapping you for the remainder of the night into the black hole, young gentleman, do you see, and have no doubt but the air of that agreeable apartment will restore your senses.’
** 1860, Herbert Spencer, Education: Intellectual, Moral, and Physical:A discipline of unlimited autocracy, upheld by rods, and ferules, and the black hole.
* (astronomy) A gravitationally domineering celestial body with an event horizon from which even light cannot escape; the most dense material in the universe, condensed into a singularity, usually formed by a collapsing massive star. [from 20th c.]
** 2019 April 10, Hannah Devlin, The Guardian:Astronomers have captured the first image of a black hole, heralding a revolution in our understanding of the universe’s most enigmatic objects.
* (figuratively) A void into which things disappear, or from which nothing emerges; an impenetrable area or subject; an area impervious to communication. [from 20th c.]
** 2000 November 26, Linda Seebach, “Unwanted e-mail belongs in an Internet black hole”, in RockyMountainNews.com:you'll have to love U.S. District Court Judge John Kane's decision to keep Denver-based Exactis.com out of an Internet black hole.... MAPS maintains a database of Internet addresses that it believes send or relay spam. It’s called the "Realtime Blackhole List"
** 2004 November 16, Jenifer Hanen, “How I fell down an Internet Black Hole....”, Black Phoebe, at www.blackphoebe.com
    I finished some client work and gave myself 30 minutes to fall down one of my favorite internet black holes: genealogical research. Four hours plus some later, my eyes were burning in my head
** 2006 October 23, Tom Zeller Jr., “The Internet Black Hole That Is North Korea”, in The New York Times:Julien Pain, head of the Internet desk at Reporters Without Borders, a Paris-based group which tracks censorship around the world, put it more bluntly. “It is by far the worst Internet black hole,” he said.
** 2019, Li Huang, James Lambert, “Another Arrow for the Quiver: A New Methodology for Multilingual Researchers”, in Journal of Multilingual and Multicultural Development, →DOI, page 7:In fact, with regards to spoken language, what we were looking at was a rather large black hole in the data, and hence was born the AOT method.
** 2021 July 28, Industry Insider, “Reject instant decision making”, in RAIL, number 936, page 84:The initial forecast about future demand for main line rail travel that has been made by the DfT is that volume is not expected to grow in the immediate future beyond 80% of the pre COVID-19 level, leaving an annual £2 billion revenue black hole compared to earlier financial forecasts.
* (aviation) A dangerous optical illusion that can occur on a nighttime approach with dark, featureless terrain between the aircraft and a brightly-lit runway, where the aircraft appears to the pilots to be higher up than it actually is, potentially triggering a premature or overly-steep descent and a crash short of the runway.
* (Internet, often attributive) A place where incoming traffic is silently discarded.
    One way of fighting spam is to use a blackhole list maintained on a blackhole server.
* (programming) A bit bucket; a place of permanent oblivion for data.

#### Antonyms

* (antonym(s) of “celestial body”): white hole

#### Hypernyms

* hole

#### Hyponyms

* collapsar
* eternal black hole
* primordial black hole
* stellar black hole

#### Coordinate terms

(celestial body):
* ergosphere
* event horizon
* photon sphere
* singularity
* spaghettification

#### Derived terms

(celestial body):
* black hole star
* blanet
* BZ black hole
* eternal black hole
* extremal black hole
* intermediate black hole
* intermediate mass black hole
* Kerr black hole
* Kerr-Newman black hole
* micro black hole
* mini black hole
* optical black hole
* primordial black hole
* regular black hole
* Reissner-Nordström black hole
* Schwarzschild black hole
* stellar black hole
* stellar mass black hole
* supermassive black hole

#### Related terms

(celestial body):
* white hole
* wormhole
(body with a characteristic emission spectrum):
* blackbody (black body)

#### Descendants

* → Bengali: ব্ল্যাকহোল (blêkhol), ব্ল্যাক হোল (blêk hol)
* → Japanese: ブラックホール (burakku hōru)
* → Korean: 블랙홀 (beullaekhol)

#### See also

(celestial body):
* collapsar
* cosmic string
* domain wall
* neutron star
* preon star
* quark star
* strange star
* white dwarf
* dumb hole

#### Further reading

* (celestial body): black hole on Wikipedia.Wikipedia

### Verb

black hole (third-person singular simple present black holes, present participle black holing, simple past and past participle black holed)
* (transitive, Internet) To redirect (network traffic, etc.) nowhere; to discard (incoming traffic).
** 2005, Victor Oppleman, Oliver Friedrichs, Brett Watson, Extreme exploits: advanced defenses against hardcore hacks, page 186:Select a nonglobally routed prefix, such as the Test-Net (RFC 3330) 192.0.2.0/24, to use as the next hop of any attacked prefix to be blackholed.

#### Coordinate terms

* bit bucket

### References

* ↑ Tom Siegfried (2013 December 23) “50 years later, it’s hard to say who named black holes”, in ScienceNews‎, Society for Science, archived from the original on 7 July 2016
* ↑ Michael Quinion (2008 April 26) “Black Hole”, in World Wide Words‎, archived from the original on 7 July 2016
* “black hole”, in Lexico, Dictionary.com; Oxford University Press, 2019–2022.